Sounds We Protect

Natural and cultural sounds awaken the sense of awe that connects us to the splendor of national parks and have a powerful effect on our emotions, attitudes, and memories. The National Park Service regards these sounds as part of a web of natural and cultural resources that must be protected.

Natural Sounds

Natural sounds are vital to the natural functioning of park ecosystems. Section 4.9, Soundscape Management, of the 2006 Management Policies, requires that we restore and manage park acoustical environments and soundscapes (see the Science of Sound page for definitions). Studies suggest that the acoustical environment is important in a number of ways including:

Bull Elk bugling. Photo by Donal Metzner

Intra-species communication

Territory establishment, finding desirable habitat

Courtship and mating

Nurturing and protecting young

Predation and predator avoidance

Effective use of habitat

The visitor who experiences the reverberating thud of male bighorn sheep butting heads, the eerie bugle of a bull elk in "rut," and the slap of a beaver tail on the water's surface often cherishes these memories for a lifetime. They are potent reminders of the ancient rituals preserved in our natural spaces and serve as key examples of the richness of park acoustical environments.

Most national park visits, however, are dominated by the songs of birds, frogs, and insects going about their daily activities. Such sounds, while more common than a bugling elk, are a captivating and memorable part of a park experience. Standing in the midst of the deafening trill of spring peepers, for example, is a riveting reminder that wetlands are critical habitat for amphibians. While most amphibians are almost impossible to spot, their calls travel for miles.

Other natural sounds promote understanding of the role of natural sounds in the ecosystem. A rattlesnake, for example, will shake its tail to alert intruders to its presence. Killdeer use a distinct, high-pitched trill, while faking a broken limb, to distract predators from their ground nests. The song of the cactus wren characterizes the desert landscape. When building nests these wrens will call out with a rapid buzz at any threat to their progress. Such examples help convey the significance of preserving the integrity of the acoustical environment.

American Goldfinch. USFWS Photo by David Brezinski

Bird songs, in general, are ideal tools for introducing young visitors to natural sounds. They are often beautiful, or even humorous, and can be heard almost anywhere. Because they can be likened to human phrases, people easily relate to them and even children can be encouraged to tune in. For example, the American goldfinch call is thought to sound like the words "potato chip!" Children easily relate to the call of the ovenbird, heard in deciduous woodlands in spring, which sounds like "teacher! teacher! teacher!"

Insects, like birds, have an endless repertoire of sounds.
Hearing the piercing whine of cicadas brings to mind hot, lazy summer days for most park visitors. Many would not be surprised to learn that male cicadas produce the loudest sounds in the insect world (actually approaching the pain threshold of the human ear). But how many know that the loud noise repels birds? Entomologists believe that the sound hurts the predators' ears.

Cultural Sounds

Culturally-based sounds help reinforce a sense of pride in place, a connection to heritage and the awareness that humans, too, are integral to soundscapes. Many anthropogenic (man-made) sounds have embedded themselves in the American psyche and echo significant movements in the country's development. The chant "No taxation without representation!" needs no explanation to the American adult. The whistle of a train, the heavy rattle of a slave's chains and the crack of musket fire are all imbued with meaning about the American experience.

Guards fire cannon at Fort McHenry. NPS Photo

Many culturally-based sounds are tangible symbols of a park's relevance. The deafening roar of the fabric looms in the factories at Lowell National Historical Park, for example, conveys the loss of autonomy experienced by factory workers who left the farm. The resonant clang of an iron spike being driven into a rail at Golden Spike National Historic Site can depict a nation linked for the first time by the railroad, while the piercing screech of sirens at Oklahoma City National Memorial evoke the sense of a country torn apart by terror. The sounds of gunshots and human cries contrasted with the silence of an empty prairie at Bear Paw Battlefield are haunting reminders of the anguish of the Nez Perce as they ceased their struggle against the white man.

Music has an undisputed ability to transport people through time and space and recreate a mood. Additionally, many pivotal moments in U.S. history are defined by a musical style. An interpretive tour of the Vietnam War Memorial might be enhanced with a recording of conflict-driven songs from the 1960s. Recordings of Native American tribal music help set a jubilant or reverent atmosphere, and the lighthearted sounds of ragtime piano can conjure the robust spirit of the gold rush days.